DOI:10.1371/journal.pone.0054508 Wide Range of Mercury Contamination in Chicks of Southern Ocean Seabirds

• Main Authors: Bustamante B, Yves Cherel A
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2013
• Subjects: Indian; Kerguelen; Kerguelen Islands; Southern Ocean
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.382.3726; http://hal.inria.fr/docs/00/77/84/91/PDF/Blevin_et_al._2013_PLOS_ONE.pdf

ABSTRACT: Using top predators as sentinels of the marine environment, Hg contamination was investigated within the large subantarctic seabird community of Kerguelen Islands, a remote area from the poorly known Southern Indian Ocean. Chicks of 21 sympatric seabirds presented a wide range of Hg concentrations, with the highest contaminated species containing ~102 times more feather Hg than the less contaminated species. Hence, Kerguelen seabirds encompass the whole range of chick feather Hg values that were previously collected worldwide in poorly industrialized localities. Using stable isotopes, the effects of foraging habitats (reflected by δ 13 C) and trophic positions (reflected by δ 15 N) on Hg concentrations were investigated. Species-related Hg variations were highly and positively linked to feather δ 15 N values, thus highlighting the occurrence of efficient Hg biomagnification processes within subantarctic marine trophic webs. By contrast, Hg contamination overall correlated poorly with feeding habitats, because of the pooling of species foraging within different isotopic gradients corresponding to distinct seabird habitats (benthic, pelagic, neritic and oceanic). However, when focusing on oceanic seabirds, Hg concentration was related to feather